I have 3Com HomeConnect cable modem and it's connected to my PC via USB. I've tried all possible USB networking drivers and CDCEther seems to be only driver that reconizes the device.

When I do "dhcpcd eth0" eth0 gets correct IP, hostname, netmask etc. from DHCP server. Everything seems to be ok. Routing tables look also correct.

My problem is that connection doesn't actually work, when I try to open web page, ping etc the modem lights starts blinking... but nothing happens. I've also tried pinging with IP address, without no luck, so this can't be a DNS configuration problem.

Could anyone please help me with this. Thanks in advance.

When booting, there appears line "eth0 -Could not get valid interface name -> Skipped". I guess that causes the problem, but how can I fix it?

eth0 is down by default (not shown in ifconfig) until I do manually "dhcpcd eth0".

Try entering "alias eth0 CDCEther" (without the quotes) in your /etc/modules.config file (if you haven't already). This will allow it to be seen at boot, at least.